1. Field of the Invention
The current invention relates in general to a hydrodynamic machine and especially a hydrodynamic coupling in a turbine compound system.
2. Description of the Related Art
As is generally known, hydrodynamic machines, such as hydrodynamic couplings, include hydrodynamic retarders, and also hydrodynamic converters include a primary wheel and a secondary wheel which together form a work space which is filled or can be filled with operating medium and in which through driving the primary wheel an operating medium circulation is caused which transfers torque or respectively power to the secondary wheel. In a hydrodynamic coupling the primary wheel is also referred to as pump wheel and the secondary wheel as turbine wheel.
Such hydrodynamic machines include a housing which can be connected to one of the two blade wheels—primary wheel or secondary wheel—and which then together with the blade wheel to which it is connected envelopes the respective other blade wheel in axial direction. Alternatively a housing can be provided which envelopes both blade wheels in circumferential and/or axial direction, whereby it is connected rotationally fixed or whereby it is stationary or whereby it circulates at a different speed than both blade wheels.
A housing which is connected to one of the two blade wheels is conventionally connected with the respective blade wheel through screw connections or by welding on. The German patent application DE 10 2004 011 521 A1 for example describes a hydrodynamic coupling in a turbine compound system in which a single component deep-drawn housing is slid over the pump wheel onto a drive gear which is connected to the pump wheel and is welded to it. This solution is however only possible without additional shaping of the housing after this is slid over the pump wheel if the point of tie-in of the housing on the drive gear has a diameter which is at least of the same dimension or larger than the outside diameter of the pump wheel. In addition, an undesirable heat input into the pump wheel could occur during the process of welding the housing to the drive gear due to the selected design which can lead to distortion of the pump wheel or to material changes in the pump wheel.
What is needed in the art is a hydrodynamic machine, especially a hydrodynamic coupling, in a turbine compound system in which a sheet metal housing can be mounted cost effectively, securely and without the mentioned disadvantages. In addition, a method for the production of a hydrodynamic machine or respectively, for the installation of an appropriate sheet metal housing, is to be cited.